Impact resistant absorbing materials are widely used in various products that are incorporated into daily life in order to reduce impact to the body in products such as bedding and sporting goods (such as running shoes); in order to eliminate the effects of vibration on the characteristics of equipment for precision equipment and acoustic devices; or in order to prevent damage to products or the like during transportation in the field of packaging materials.
Conventionally, these impact resistant absorbing materials have primarily been made of rubber or polyurethane foam, but in order to achieve greater impact absorbency, the use of gels as impact resistant absorbing materials has been under investigation lately. For example, organogels, which contain oil in a resin, or silicone gels, which contain silicone oil, are known to be gels of this type.
Japanese Unexamined Patent Application 2001-151979 discloses a gel composition with excellent impact absorption characteristics produced by blending mineral oil, castor oil, or cottonseed oil or the like as a softening agent with a triblocked styrene based elastomer and a diblocked styrene based elastomer. Furthermore, Japanese Patent Disclosure H7-3165 discloses a manufacturing method for a porous silicone gel suitable for use as an impact resistant material for sports shoes.
On the other hand, the development of ionic liquids has been proceeding in fields that are entirely different from impact resistant absorbing materials. Ionic liquids are also referred to as ambient temperature molten salts and are liquids at ambient temperature. They are primarily used as electrolytic solutions for various electrochemical devices such as lithium rechargeable batteries and the like because of the high ionic conductivity and non-volatility. Furthermore, the development of gel electrolytes using ionic liquids has also been under investigation recently in order to prevent liquid leaking from the device. Japanese Unexamined Patent Application 2005-179551 discloses a gel electrolyte that is used as an electrolyte for electrochemical devices such as lithium rechargeable batteries and electrochromic display elements and the like.